18-51058150-C-T

Variant names:

• chr18-51058150-C-T
• rs765597059
• NM_005359.6:c.693C>T

Variant summary

Our verdict is Benign. The variant received -21 ACMG points: 0P and 21B. BP4_Strong BP6_Very_Strong BP7 BS1 BS2

The NM_005359.6(SMAD4):​c.693C>T​(p.Gly231Gly) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000446 in 1,613,934 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. G231G) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000047 (0 hom.)
• Consequence: SMAD4 NM_005359.6 synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:12
• Conservation: PhyloP100: 1.40
• Publications: 1 publications found

Genes affected

SMAD4 (HGNC:6770): (SMAD family member 4) This gene encodes a member of the Smad family of signal transduction proteins. Smad proteins are phosphorylated and activated by transmembrane serine-threonine receptor kinases in response to transforming growth factor (TGF)-beta signaling. The product of this gene forms homomeric complexes and heteromeric complexes with other activated Smad proteins, which then accumulate in the nucleus and regulate the transcription of target genes. This protein binds to DNA and recognizes an 8-bp palindromic sequence (GTCTAGAC) called the Smad-binding element (SBE). The protein acts as a tumor suppressor and inhibits epithelial cell proliferation. It may also have an inhibitory effect on tumors by reducing angiogenesis and increasing blood vessel hyperpermeability. The encoded protein is a crucial component of the bone morphogenetic protein signaling pathway. The Smad proteins are subject to complex regulation by post-translational modifications. Mutations or deletions in this gene have been shown to result in pancreatic cancer, juvenile polyposis syndrome, and hereditary hemorrhagic telangiectasia syndrome. [provided by RefSeq, May 2022]

SMAD4 Gene-Disease associations (from GenCC):

• juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: ClinGen, PanelApp Australia, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp
• Myhre syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, PanelApp Australia, G2P, Orphanet
• generalized juvenile polyposis/juvenile polyposis coli

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet
• juvenile polyposis syndrome

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• familial thoracic aortic aneurysm and aortic dissection

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• hereditary hemorrhagic telangiectasia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• pulmonary arterial hypertension

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ENSG00000267699 (HGNC:):

ACMG classification

Our verdict: Benign. The variant received -21 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.49).
• BP6: Variant 18-51058150-C-T is Benign according to our data. Variant chr18-51058150-C-T is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 215844.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=1.4 with no splicing effect.
• BS1: Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.0000197 (3/152158) while in subpopulation NFE AF = 0.0000441 (3/68044). AF 95% confidence interval is 0.0000117. There are 0 homozygotes in GnomAd4. There are 2 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
• BS2: High AC in GnomAdExome4 at 69 AD gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005359.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SMAD4	NM_005359.6	MANE Select	c.693C>T	p.Gly231Gly	synonymous	Exon 6 of 12	NP_005350.1	Q13485
	SMAD4	NM_001407041.1		c.693C>T	p.Gly231Gly	synonymous	Exon 6 of 12	NP_001393970.1	A0A024R274
	SMAD4	NM_001407042.1		c.693C>T	p.Gly231Gly	synonymous	Exon 6 of 12	NP_001393971.1	Q13485

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SMAD4	ENST00000342988.8	TSL:5 MANE Select	c.693C>T	p.Gly231Gly	synonymous	Exon 6 of 12	ENSP00000341551.3	Q13485
	SMAD4	ENST00000591126.5	TSL:1	n.2694C>T		non_coding_transcript_exon	Exon 2 of 8
	SMAD4	ENST00000714264.1		c.693C>T	p.Gly231Gly	synonymous	Exon 6 of 12	ENSP00000519545.1	A0AAQ5BHY6

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152158 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000441

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000358 AC: 9 AN: 251160 AF XY: 0.0000516

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000704

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.0000472 AC: 69 AN: 1461776 Hom.: 0 Cov.: 32 AF XY: 0.0000495 AC XY: 36 AN XY: 727192

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.0000374 AC: 2 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.0000567 AC: 63 AN: 1111908

Other (OTH) AF: 0.0000662 AC: 4 AN: 60394

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152158 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74334

African (AFR) AF: 0.00 AC: 0 AN: 41418

American (AMR) AF: 0.00 AC: 0 AN: 15276

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5198

South Asian (SAS) AF: 0.00 AC: 0 AN: 4834

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10600

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000441 AC: 3 AN: 68044

Other (OTH) AF: 0.00 AC: 0 AN: 2090

Alfa AF: 0.0000286 Hom.: 0

Bravo AF: 0.0000264

EpiCase AF: 0.00

EpiControl AF: 0.000178

ClinVar

ClinVar submissions

Significance: Benign/Likely benign

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	-	3	not specified (3)
-	-	2	Juvenile polyposis syndrome (2)
-	-	2	Juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome (2)
-	-	2	not provided (2)
-	-	1	Hereditary cancer-predisposing syndrome (1)
-	-	1	Hereditary cancer-predisposing syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection (1)
-	-	1	SMAD4-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.49
CADD	Benign	15
DANN	Benign	0.57
PhyloP100		1.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=100/0	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs765597059; hg19: chr18-48584520;